1. Field of the Invention
The present invention relates to a body leaning control system for use on a saddle riding type vehicle having a pair of traveling members at least at the front or rear portion of a vehicle body, which can make turns by leaning the vehicle body, and also relates to a saddle riding type vehicle including such the body leaning control system.
2. Description of the Related Art
A saddle riding type vehicle has heretofore been proposed that has a pair of wheels (traveling members) arranged at both the front portion and/or rear portion of the vehicle body, and a support mechanism for supporting at least one pair of wheels to be movable up and down relative to the vehicle body. The saddle riding type vehicle constructed in this way can make turns by leaning the vehicle body as does a motorcycle (as disclosed in Japanese Unexamined Patent Publication No. 2004-359232, Japanese Unexamined Patent Publication S59-179467 and Japanese Unexamined Patent Publication S58-188771, for example).
Japanese Unexamined Patent Publication No. 2004-359232 discloses a three-wheeled automotive vehicle having a pair of wheels provided at the front of a vehicle body. A support mechanism supporting the pair of wheels includes a group of rolls held to form a shape of an articulated square by two crossbars arranged vertically and rotatably supported at the forward end of a main frame, a right side tube connected to right ends of both crossbars, and a left side tube connected to left ends of both crossbars. The pair of right and left tubes rotatably support the pair of wheels. The support mechanism constructed in this way supports the pair of wheels to be movable up and down relative to the vehicle body. Thus, the vehicle disclosed in Japanese Unexamined Patent Publication No. 2004-359232 can make turns while leaning the main frame with the pair of wheels contacting the traveling surface.
Japanese Unexamined Patent Publication S59-179467 and Japanese Unexamined Patent Publication S58-188771 each disclose a three-wheeled automotive vehicle having a pair of wheels at the rear of a vehicle body. The pair of wheels are rockably supported by a main frame. The vehicle further includes a device for limiting rocking of the pair of wheels, and a device for detecting vehicle speed, for limiting the rocking when the vehicle speed falls to a certain fixed speed. This stabilizes the position of the vehicle body when stopping, for example.
However, the conventional vehicles with such constructions have the following drawbacks and disadvantages.
With the conventional constructions, the rocking is limited when the vehicle speed falls to a fixed speed, and whether to carry out the rocking limitation is not related to lean angles of the vehicle body. Therefore, the rocking limitation may not take place even when the vehicle body leans to an excessive degree. In order to return the vehicle body to a neutral position when the vehicle body leans to an excessive degree, the rider carries out accelerator control and steering control, and/or changes his or her riding position to shift the center of gravity (hereinafter called “return control” as appropriate). However, such return control imposes a burden on the rider when the vehicle body leans to an excessive degree, which can cause an inconvenience of impairing a comfortable run.